1. Field of the Invention
This invention is generally directed to compact blower and filter assemblies for introducing a filtered air flow to enclosed environments wherein the blower and filter are mounted within a rectangular housing in close proximity to one another and are separated by an intermediate baffle. More particularly, the invention is directed to improvements which reduce the noise and vibration level and improve air uniformity associated with the air passing through such blower and filter assemblies by the use of deflectors associated with the intermediate baffle and walls of the housing which deflectors direct the flow of air moving radially outwardly relative to the blower away from the corners of the housing as the air passes around the intermediate baffle and toward the filter.
2. History of the Related Art
U.S. Pat. No. 4,560,395 to Davis discloses a compact blower and filter assemblies which are used to purify air in an enclosed environment. The air filter units may be ceiling mounted or mounted to the upper portion of work stations or work cabinets. Each unit includes a generally rectangular housing in which an internal blower directs incoming air outwardly toward the ends of the housing. An internal baffle assists in directing the air toward the end of the housing after which the air is directed toward a discharge from the housing through a filter.
Although this type of blower and filter assembly operates comparably quieter and with less vibration than previous blower and filters utilized to purify air in enclosed environments, there remain operative characteristics of such assemblies which do create undesirable noise and vibration.
It has been observed through various tests, that various motor imbalances lead to vibration of the housing of such filter assemblies. Further, the blowers when rotating actually function to generate noise as they direct sound waves toward the internal baffle. Further, because of the rectangular configuration of such assemblies, air is directed along the interior sidewalls into the corners of the housing where a great deal of turbulence is created.